• Journal of the Korean Operations Research and Management Science Society
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• v.25 no.4
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• pp.81-95
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• 2000

A knowledge-based system with fuzzy production rules is a representation of static knowledge of an expert. On the other hand, a real system such as the stock market is dynamic in nature. Therefore we need a strategy to reflect the dynamic nature of real system when we make inferences with a knowledge-based system. This paper proposes a strategy of dynamic inferencing for a knowledge-based system with fuzzy production rules. The strategy suggested in this paper applies weights of attributes of conditions of a rule in the knowledge-base. A degree of match(DM) between actual input information and a condition of a rule is represented by a value [0,1]. Weights of relative importance of attributes in a rule are obtained by AHP(Analytic Hierarcy Process) method. Then these weights are applied as exponents for the DM, and the DMs in a rule are combined, with MIN operator, into a single DM for the rule. In this way, overall DM for a rule changes depending on the importance of attributes of the rule. As a result, the dynamic nature of a real system can be incorporated in an inference with fuzzy production rules.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.40 no.8
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• pp.731-740
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• 1991

This paper presents a knowledge based system to solve reactive power/voltage control problem in a power system. The methods to reduce inference time are proposed in inferring the solution of problem in the knowledge base which consists of heuristic rules and inowledge of experts. A set of indices drawn from the heuristic knowledge on the power system is utilized to make up for the defect of existing knowledge based systems which determine both the location and the amount of reactive power compensation devices. The concept of set of indices developed in this paper makes it possible to infer the amount of reactive power source only since the bus order list representing priority for the location of reactive power compensator to be switched on can be determined in advance. From the fact that there exists a relationship between the system voltage pattern and the reactive power pattern in operation, the pattern recognition technique is introduced to reduce the inference time in solving the severe voltage problem. To demonstrate the usefulness of the proposed knowledge based system, the IEEE 30 bus system is chosen as a sample system. The results of case study are also presented.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.12
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• pp.2134-2145
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• 1997

We present a framework of an intelligent design system for embodiment design of machine tools which can support efficiently and systematically the machine design by utilizing design knowledge such as objects(part), know-how, public, evaluation, and procedures. The design knowledge of machining center has been accumulated through interview with design experts of machine tool companies. The processes of embodiment design of machining center are established and represented by the IDEF0 model from the field surveys. We also introduce a hybrid knowledge representation so that the system can easily deal with various and complicated design knowledge. The intelligent design system is being developed on the basis of object-oriented programming, and all parts of a design object, machining center, are also classified by the object-oriented modeling.

• The Journal of Korean Academic Society of Nursing Education
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• v.21 no.1
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• pp.108-118
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• 2015

Purpose: The purpose of this study was first to identify knowledge about, attitude toward, and educational needs for dementia in certified caregivers; secondly, to understand the relationships among those variables; and thirdly, to provide base-line data for education program development. Methods: The participants in this study were 670 certified caregivers who were working in nursing homes or care hospitals throughout the whole of the country and engaged in education programs for improvement of their professional abilities. Collected data were analyzed using t-tests, ANOVA, Duncan, and Pearson's correlation coefficients with the SPSS 18.0 for Windows Program. Results: The scores for knowledge about, attitude toward, and educational needs for dementia were $14.12{\pm}2.83$ out of 20, $42.27{\pm}5.54$ out of 50 (item mean 4.22), and $121.51{\pm}22.13$ out of 160 (item mean 3.79) respectively. There were statistically significant positive correlations between knowledge and attitude (r=.238, p<.001), educational needs (r=.083, p=.032), and attitude and educational needs (r=.244, p<.001). Conclusion: Tailored and continuous educational programs for certified caregivers that can improve knowledge about the causes and symptoms of dementia should be developed. Nurses and professors who are experts in dementia should be on the front lines of education for caregivers.

• Journal of the Society of Naval Architects of Korea
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• v.30 no.2
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• pp.30-36
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• 1993

An expert system to help a novice engineer in designing midship section is developed. The system is developed based on a general-purpose expert system shell, NEXPERT. Firstly, the design knowledge is extracted from an existing rule scantling program. The knowledge has been grouped and structured into a hierarchy by applying object-oriented concepts. Secondly, the knowledge base is integrated with a database of existing ships and engineering analysis modules through the Application Programming Interface(API)technique. Graphical User Interface which is developed using Motif wiget set is adopted. These altogether enable construction of an user friendly expert system.

• Journal of the Korean Society for information Management
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• v.6 no.1
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• pp.93-117
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• 1989

The objective of this study is to design an automatic abstracting system through the analysis of natural language texts. For this purpose a knowledge-based system operating on the basis of domain knowledge was developed. The procedure of generating an abstract consists of three steps: (1) A knowledge-base containing domain knowledge necessary to understand a text is constructed using frame and semantic network structures,and preliminary abstracts are prepared for various cases. (2) Input text is analysed on the basis of domain knowledge in order to extract information filling slots of the abstract with. (3) A Preliminary abstract corresponding to the input text is called and filled with the information, completing the abstract.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.440-443
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• 2005

The wide spread of internet business recently necessitates recommendation systems which can recommend the most suitable product fur customer demands. Currently the recommendation systems use content-based filtering and/or collaborative filtering methods, which are unable both to explain the reason for the recommendation and to reflect constantly changing requirements of the users. These methods guarantee good efficiency only if there is a lot of information about users. This paper proposes an algorithm called 'demand articulate & integration' which can perceive user's continuously varying intents and recommend proper contents. A method of knowledge classification which can be applicable to this algorithm is also developed in order to disassemble knowledge into basic units and articulate indices. The algorithm provides recommendation outputs that are close to expert's opinion through the tracing of articulate index. As a case study, a knowledge base for heritage information is constructed with the expert guide's knowledge. An intelligent recommendation system that can guide heritage tour as good as the expert guider is developed.

• Journal of the Korean Data and Information Science Society
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• v.20 no.6
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• pp.1177-1190
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• 2009

In this paper, we propose a fuzzy proxy cache scheme for caching web documents in mobile base stations. In this scheme, a mobile cache model is used to facilitate data caching and data replication. Using the proposed cache scheme, the individual proxy in the base station makes cache decisions based solely on its local knowledge of the global cache state so that the entire wireless proxy cache system can be effectively managed without centralized control. To improve the performance of proxy caching, the proposed cache scheme predicts the direction of movement of mobile hosts, and uses various cache methods for neighboring proxy servers according to the fuzzy-logic-based control rules based on the membership degree of the mobile host. The performance of our cache scheme is evaluated analytically in terms of average response delay and average energy cost, and is compared with that of other mobile cache schemes.

• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.4
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• pp.166-175
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• 2001

The high speed tracking control of a 6-6 Stewart platform manipulator (SPM) normally requires knowledge of its complex full dynamics and measurement of its base motion when the SPM operates on a motion nit. In this study, an enhanced sliding mode control scheme has been developed, which is based on the reduced dynamics, not necessitating measurement of the base motion. The enhanced sliding mode control implemented with the perturbation compensation and modified reaching phase alleviation functions has been successfully employed for high speed tacking control of the laboratory SPM, when it is subjected to a virtual base motion.

• Journal of Korean Society for Quality Management
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• v.20 no.1
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• pp.91-100
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• 1992

A diagnosis system for naphtha reforming process has been designed and implemented using expert system building technique. The system is composed of knowledge base, inference engine, user interface, database and database interface. The concept and the method of this system may be applied to development of other systems for the reforming process.